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Return an > error if `allocate_command` is called with a too large size. > > Signed-off-by: Eliot Courtney > --- > drivers/gpu/nova-core/gsp/cmdq.rs | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gs= p/cmdq.rs > index baae06de0e09..dbc9e95f1b17 100644 > --- a/drivers/gpu/nova-core/gsp/cmdq.rs > +++ b/drivers/gpu/nova-core/gsp/cmdq.rs > @@ -122,6 +122,11 @@ fn read( > /// Number of GSP pages making the [`Msgq`]. > pub(crate) const MSGQ_NUM_PAGES: u32 =3D 0x3f; > =20 > +/// Maximum size of a single GSP command in bytes. > +/// > +/// A single command can span up to 16 GSP pages. > +pub(crate) const MSGQ_MSG_SIZE_MAX: usize =3D GSP_PAGE_SIZE * 16; Where does this limitation come from? Is there a value in OpenRM that we can add to the bindings as the source of truth? > + > /// Circular buffer of a [`Msgq`]. > /// > /// This area of memory is to be shared between the driver and the GSP t= o exchange commands or > @@ -329,8 +334,11 @@ fn allocate_command(&mut self, size: usize) -> Resul= t> { > /// # Errors > /// > /// - `ETIMEDOUT` if space does not become available within the time= out. > - /// - `EIO` if the command header is not properly aligned. > + /// - `EIO` if the command header is not properly aligned or sizing = is impossible. `sizing is impossible` should be its own error - probably `EMSGSIZE` (which would need to be added to `kernel/error.rs` in its own patch). Also the wording sounds a bit confusing to me, why not say "if the command is larger than `MSGQ_MSG_SIZE_MAX`"?